From Longman Dictionary of Contemporary Englishshoehornshoe‧horn, shoe-horn /ˈʃuːhɔːn $ -hɔːrn/ noun [countable] DCCa curved piece of metal or plastic that you put inside the back of a shoe when you put it on, to help your heel go in easily
Examples from the Corpus
shoehorn• She was wearing biker leathers and cowboy boots which all looked as if they'd been applied with the aid of a shoehorn. 